1. Field of the Invention
This invention relates to a current supply connector comprising a plug socket having pivotal contact-strips as well as to a plug having a push-rod unit, said connector being primarily intended for operation at high current intensities.
2. Description of Prior Art
As disclosed in U.S. Pat. No. 4,249,787, it is already known to construct a connecting device providing end contact pressure and especially a current supply connector comprising a socket and detachable plug each provided with at least one contact-pin, thus forming at least one pair of pins to be placed in contact with each other.
In one device of the type described in the patent cited above, each pair of contact-pins is provided with at least one contact-strip of conductive material. Provision is made on each contact-strip face for at least one protuberance in the form of a boss or contact-stud which is intended to bear on the end face of one contact-pin of said pair when the plug and the socket are in the connection position. Each contact-strip is pivotally actuated by at least one spring which is retained by fixing or keying at one end on a component or element of the plug socket in such a manner as to ensure that each contact-stud of each contact-strip is urged towards its corresponding contact-pin.
A device of this type makes it possible in particular to obtain all the advantages of contacts applied endwise under pressure.
It is in fact a known principle established by a physical law that contact resistances can be determined by an inverse function of the contact force, which explains the attractive character of all end contacts on which a pressure can be exerted with a view at achieving more efficient flow of current.
Furthermore, this device circumvents the disadvantages arising from the conductive braided-wire elements which are usually employed in end contact devices. For example, disadvantages appear at the level of connections and are also present in the fabrication of braided wires.
However, the embodiments described in the patent cited earlier do not propose any particular means for interlocking the plug and socket or any particular connection operation. By way of example, the cited patent is more especially concerned with a bayonet-type attachment for a single-wire connection in which relative locking of the plug and socket as well as contact-making are both achieved at the same time by the plug-inserting operation.
In the high-current connectors employed in industry or in harbor installations, for example, the connecting cables of the detachable plug necessarily have large cross-sectional areas which make it fairly difficult to handle the plug. It is therefore an advantage to reduce the relative movements of the plug and of the plug socket and to facilitate the contact-making operation which often entails the need to exert a considerable effort.
This problem is solved by means of the device described in French Pat. No. FR 2466111, for example. This patent proposes a current supply connector in which the plug and the plug socket are first locked in position with respect to each other, an electrical contact being then made by means of a plug thrust member so arranged that the movable contact-pins mounted in the plug are thrust towards the socket contacts.
An arrangement of this type also offers further advantages such as, for example, perfect sliding motion of the movable contacts of the plug independently of the sliding motion of the plug and plug socket. The result thereby achieved is that a quick break can be obtained by suitable means without any attendant danger of jamming. Furthermore, the plug can be fitted within the plug socket practically without play and in a relatively fluid-tight manner, which is particularly advantageous in inflammable or explosive environments.
It proves necessary in this device, however, to provide movable contact-pins entailing the use of conductive braided-wire elements which are subject to drawbacks in comparison with the strip-type contacts mentioned earlier.